Absorbent articles, such as sanitary napkins, pantiliners, breast pads, and incontinence pads are secured to a user's garment during use. Such attachment is typically accomplished using an adhesive that has been coated on the garment-facing surface of the absorbent article. Such adhesive is typically tacky upon curing. Due to the tacky properties of such adhesive, the adhesive coating is prone to adhering dirt, dust and the like before the adhesive article is place in its desired location. Such adhesion reduces the surface area of the adhesive coating available for securing the absorbent article in place, which reduces the stay-in-place properties of the absorbent article having adhesive coating on the garment-facing surface.
Several solutions have been proposed to overcome such problems with adhesive coatings that are tacky to the touch. One common solution is to provide a separate release strip, e.g., release paper, that covers the adhesive coating prior to securing the absorbent article to the garment. The release strip acts as a protective barrier for the adhesive coating during manufacture, package, and storage of the absorbent article.
The release strip typically used in the art is a silicone-coated material, e.g., paper, which permits easy removal of the release strip from the garment facing side of the product due to the nonstick characteristic of silicone. Examples of a release paper are described in U.S. Pat. No. 4,917,697.
These proposed solutions suffer from several drawbacks for both the user of the absorbent article and the manufacturer of the absorbent article. For the user, the release strip must be removed just prior to application of the product. Such a process can be clumsy, untimely, and is a source of possible embarrassment in certain situations. For the manufacture, the inclusion of release paper adds cost and time for the manufacture of such absorbent articles. Additionally, noise is generated upon the removal and disposal of release paper.
U.S. Pat. No. 5,474,818 discloses the elimination of release paper as another attempted solution. This document discloses a method for the formation of flexible containers such as pouches, bags, or envelopes which have an interior surface coated with a composition which has nonstick characteristics and which lacks the thermoplastic characteristics of conventional heat sealing for forming seams by heat sealing. The document also discloses that the pouch is formed from a silicone polymer coated paper with the silicone coating forming an internal surface of the pouch, thereby allowing easy removal of the product from the pouch and avoiding permanent sticking of the pressure sensitive adhesive coating to the pouch material.
This proposed solution also suffers from several drawbacks. The absorbent article must be packaged in a flexible container. This creates a disposal problem for the user and increases costs for the manufacturer.
EP 1 147 756 discloses another solution that uses a substantially tack-free, high-coefficient of friction backsheet having at least one tape tab affixed to its outwardly disposed surface. Such design overcomes the problem of shifting and separation from an undergarment when the user urinates or initiates usage of the article for the first time. However, this solution is economically disadvantageous for the manufacturer.
It is known that EP 0 737 462 A1 discloses a sheet material for use in absorbent articles, whose visual and tactile properties are closer to those of a piece of fabric, whilst allegedly retaining all the typical advantages of plastic film. Such film is described as being used to cover the outside of an absorbent product, wherein at least part of the surface outside of the absorbent product contains a layer of fibers applied by flocking in order to give the absorbent product improved tactile properties over products that employ plastic films against the skin.
Flocking is a technique primarily used in the fabric industry by which fibers are fixed in a vertical position on a substrate. Recently, however, flocking has been described in conjunction with absorbent articles. For example, EP 0 737 462 A1 discloses the use of a sheet material to cover the outside of an absorbent product, wherein at least one portion of sheet material bears a layer of fibers applied by flocking, “i.e. anchored to the surface of the sheet material by a layer of resin or other adhesive and aligned substantially at right angles to the surfaces of the [ ]laminated material to cover the outside of an absorbent product, wherein at least one portion of the surface of the laminated material bears a layer of fibers applied by flocking.” According to this document, the flocked fibers are located on the external surface of the absorbent product in order to give the absorbent product improved tactile properties over products that employ plastic films against the skin. However, due to flocking fibers at substantially right angles to the surface of the substrate, articles having such flocked fibers on the garment facing side do not have sufficient adhering properties to maintain an absorbent article in place during use.
What is needed, therefore, is a system for securing the absorbent article to a garment that overcomes the above problems. The instant invention accomplishes this goal in a user-friendly and economical way. It is has surprisingly been discovered that a garment facing surface of an absorbent article essentially having a substantially tack-free adhesive and flocked fibers adhered thereon provides such a solution.
Additionally, absorbent articles having a flocked garment-facing surface may be stacked upon each other, forming a multiple layered absorbent article.